Mortgage Calculator

What will your monthly mortgage payment actually be, and can you afford it? These are the two most important questions for any Singapore property buyer, and most people rely on back-of-the-envelope guesses or the bank’s quoted figure. This calculator gives you the exact answer — plus shows you the total interest you will pay over the life of your loan, which is often a jaw-dropping number.

Enter your property price, down-payment percentage, interest rate and loan tenure, and the calculator instantly works out your monthly instalment, the total interest you will pay across the full loan, and — if you add an expected rental figure — whether the property runs at a positive or negative monthly cash flow. Results update live as you adjust any input, so you can run dozens of what-if scenarios in seconds without reloading the page.

Under the hood it uses the standard Singapore bank amortisation formula: fixed monthly payments split between principal and interest, with the interest share shrinking and the principal share growing over the life of the loan. The amortisation schedule below the results shows you year-by-year how your balance declines, and the chart visualises the split between principal and interest for every year of the tenure.

Whether you are buying your first home, weighing a second investment property, or stress-testing an existing mortgage against a potential refinance, understanding your monthly obligation down to the dollar is non-negotiable. This is the starting point for every other calculation on ShiokNest — once you know your payment, you can plug it into the TDSR calculator, the cash flow projection, and the ROI calculator to see the full picture.

Your mortgage payment is the number you live with every single month for 20–30 years. Getting it wrong by even a few hundred dollars can be the difference between financial comfort and constant stress — and the gap between a good investment and a drain on your savings. In Singapore’s high-price market, where a typical condo loan easily tops $1M, the numbers compound fast.

The most important thing this calculator reveals is the true cost of interest. On a $1.125M loan at 3.5% over 25 years, total interest exceeds $564,000 — roughly half the loan amount again, paid out in money that builds zero equity. Most buyers never see that number before they sign because banks quote only the monthly figure. A shorter tenure, even by five years, can strip six-figure sums off that total.

Interest-rate sensitivity is the second reason this matters. Singapore mortgage rates have ranged from under 1.5% during the post-2020 liquidity era to above 4% in 2023. A 1% rate rise on a $1.125M, 25-year loan adds roughly $580 to the monthly payment — about $7,000 per year — and most borrowers only discover their exposure when their lock-in period ends and the loan resets to SORA-pegged floating rates. Running a rate-shock scenario in this calculator before you commit tells you whether you can still afford the loan at 5%.

For investment properties, the cash-flow comparison is the make-or-break number. If your monthly rent covers only 60–70% of the mortgage, you are writing a cheque every month from your salary to hold the property — fine if you expect capital gains, dangerous if rates rise or tenants default. The calculator’s cash-flow field shows you that gap in a single line, so you can size your deposit, choose a tenure, or walk away from a deal before you are locked in.